Sinker operating mechanism for knitting machines



Oct. 6, 1959 J. HELD 2,907,192

SINKER OPERATING MECHANISM FOR KNITTING MACHINES Filed Jan. 25, 1955 2 Sheets-Sheet 1 INVENTOR.

Jose h [#141 if. 0%,,

ATTORNEY.

Oct. 6, 1959 J. HELD 2,907,192 SINKER OPERATING MECHANISM FOR KNITTING MACHINES Filed Jan.- 25, 1955 2 Sheets-Sheet 2 IN VEN TOR.

BY Jose hffilJ M .Q.

ATTORNEY.

United StatcS Patent SINKER OPERATING MECHANISM FOR KNITTING MACHINES Application January 25, 1955, Serial No. 483,906

Claims. (Cl. 6686) This invention relates to tricot knitting machines and more particularly to means for improving a correlation of the needles and sinkers of such machines during their loop forming operations.

. In certain of the present tricot knitting machines, needles are employed of the type having latches or tongues for closing their hook portions; In one type of such machines adapted for high speed operation, the needles, sinkers and other elements participating in the knitting of yarns into loops, are operated by two eccentric shafts one of which is operated at twice the speed of the other. The needles and sinkers are connected by lever systems to both of the eccentric shafts and the resulting motions of both shafts are transmitted through the levers to move the needles and sinkers along the desired cooperating paths. In this machine the path of the needles is along a substantially straight vertical line which requires only a relatively simple cooperating movement of the sinkers readily obtainable by the mechanism provided.

In another form of high speed tricot machine spring bearded needles are employed which are also operated by eccentric shafts rotated at different speeds. In this machine the needles must be given both vertical and.

lateral movements in forming the loops into a knitted fabric. Consequently, in order to maintainthe necessarily close cooperation between the needles and sinkers, the sinkers mustbe given additional movementswhich should desirably correspond to the lateral movements of the needles to maintain a substantially fixed lateral relationship between them during portions of their travel. Heretofore such fixed relationship has not been possible with the known mechanisms.

It is accordingly an object of the invention to provide a tricot knitting machine having spring bearded needles with improved mechanism for coordinating the movement of the sinkers with both the vertical and lateral movements of the needles.

, Another object of the invention is to provide a tricot knitting machine, having eccentric operating shafts, with means operated by the eccentric shafts which will eliminate the difiiculties heretofore encountered in coordinating the movement of the sinkers with both vertical and lateral movements of the needles.

A still further object is to provide means for operating the sinkers in a tricot knitting machine which includes a connection between the sinkers and an eccentric shaft A 2,907,192 Patented Oct. '6, 1959 parts, as hereinafter more particularly pointed out in the claims.

In the drawings:

Figure 1 is a cross sectional view taken transversely through a tricot knitting machine showing the yarn guiding and loop forming elements and including means according to the invention for operating the sinkers;

Fig. 2 is a view of a portion of the mechanism of Fig. l and taken substantially along the line 22 of Fig. 1;

Fig. 3 is an elevational view as seen from the right of Fig. 1, parts being omitted and others being broken away and shown in cross section;

. Fig. 4 is a cross sectional view taken along the line 4-4 of Fig. 1;

Fig. 5 is a cross sectional view taken along the line 5 5 of Fig. 2; i

- Fig. 6 is a view on an enlarged scale illustrating the relative positions of the yarn guiding and loop forming elements at one stage in a knitting cycle, and diagrammatically showing the path of the needle; and

Figs. 7 to 11 are views similar to Fig. 6, showing the elements at other stages in a knitting cycle.

Referring to the drawings and more particularly to Fig. 1, there is shown the usual yarn feeding and loop forming elements of a tricot knitting machine including spring beard needles 15 carried in a needle bar 16, sinkers 17, carried on a bar 18, a presser plate 20 for closing the beards of the needles and yarn guides 21 for feeding yarns to the needles. The needles 15, presser plate 20 and yarn. guides 21 are of a common form and are operated by means including a shaft 22 rotated at machine speed and a second shaft 25 which is rotated at twice the speed of the shaft 22. The means for operating the needles 15,

operating at one speed for moving the sinkers through accompanying drawings, the invention resides in the novel 7 n elements, features of construction and cooperation of presser plate 20 andyarn guides 21, other than the shafts 22 and 25, form no part of the present invention and are not shown herein but are of the type shown and described in my copending application Serial No. 378,852, filed September 8, 1953.

In the instant invention, the bar 18 carrying sinkers 17 is secured by bolts 26 to a plurality of spaced similar levers, one of which is shown at 27 in Figs. 1 and 2. Each lever 27 is carried on a shaft 30 mounted for free oscillating movement in the framework of the machine as for example as shown for the shaft 122 in said copending application. The bearing portion of the lever 27, surrounding'the shaft 30, is split at 31 and a screw or bolt 32 passing through one of the split portions and threaded in the other portion acts to clamp the lever to the shaft. The lever 27 is positioned intermediate a pair of arms 35 loosely mounted on the shaft 30; An adjusting screw-36 is provided in each arm 35 to adjust the position of the arms relative to the lever 27. The arms 35 and lever 27 are clamped together in adjusted position by a bolt 37 extending through openings 34 in the .arms and an opening 39 in the lever which is enlarged with respect to the diameter of the bolt (Fig. 5) to permit the adjustment to take place. A nut 38 threadably carried on the bolt (Figs. 2 and 5) exerts the clamping action.

.The free ends of the arms 35 are pivotally connected by a pin 40 to one end of a link 41, the other end of which is pivotally connected by a pin 42 to a forked end 44 of a rigid crank lever 45 (Figs. 1 and 3). The other end of the lever 45 has a split type bearing portion 46 which is provided with a bore 47 for rotatableengagement with an eccentric portion 50 of the shaft 25 intermediate collars or flanges 49 formed on the shaft (Fig. 4). ,The lever 45 and link 41 form a toggle joint between the arms 35 and shaft 25 by means of which the lever 27 and sinkers 17 are oscillated about the axis of theshaft 30. ateach rotationof'theshaft 25. v

In accordancewith the invention it is desirable to modify the oscillating movement of the sinkers 17 as transmitted thereto by the eccentric shaft portion 50. For this purpose, a strap element 51 is provided having one end pivotally connected by means of a pin 52 to the lever 45 intermediate its ends. The other end of the strap element 51 is in the form of a split bearing 55 having a bore 56 interfitting an eccentric portion 57 of the shaft 22 intermedi'ate flanges 58 formed on the shaft. The eccentric portion 57 imparts a reciprocating movement to the strap element 51 to oscillate the lever 45 about the axisof the eccentric portion 50 of the shaft 25 and hence change the angular relation between the lever 45 and link 41 of the toggle joint. Thus the movements of lever 27 and of the sinkers carried thereby as imparted by eccentric 50 are modified by the angular adjustment of lever 45 through the action of eccentric 57. As will be understood the degree and direction of eccentricity of the portion 57 will be made to obtain the desired specific relationships between the needles and sinkers described below.

Figs. 6 to 11, inclusive, show the needles in a series of different positions during a knitting cycle and the relative position to which the sinkers are moved by the combined operations of shafts 22 and 25, as hereinbefore set forth, for each needle position. Fig. 6 diagrammatically shows the path followed by the needles 15 which substantially correspond to the path followed by the needles in the above referred to copending application. In this figure, the needles 15 are at the lowest point in their path and moving to the right in the direction of the arrow after drawing the new yarn loops through the previously formed loops of the fabric (shown in dot-and-dash outline) and casting the latter off and the sinkers 17 are moving toward their right hand limiting position. As the needles move toward the right and upwardly, the sinkers also move to the right to position a throat portion 60 of the sinker a predetermined distance from the needle as shown in Fig. 7, to maintain the length of the yarn loops initially drawn by the needles when in the position shown in Fig. 6. From Fig. 7 to Fig. 8, the needles rise and move to the point 61 of the needle path at which point the yarn guides 21 are moved through the needles and back again to lap the yarns around the needle heads for the new loops. At this time the sinkers 17 also are moved to their left hand limit to maintain a substantially constant distance between the needles and the throats 60 of the sinkers to avoid deformation of or strain on the loops by the needle shanks. From Fig. 8 to Fig. 9, the needles move toward the right and upwardly to their highest position indicated at 62 in Fig. 9 and the sinkers are moved toward the right to maintain the constant distance between the needles and the throats of the sinkers. At this time the yarns, which are wrapped around the needles to become the new loops, are just below the tips-of the needle beards.

As the cycle continues, the needles move downwardly and towards the left to the position of Fig. 10 with the yarn drawn into the needle hooks. This is the position of the needles just prior to their engagement with the presser plate 20 to close their beards. At this time the sinkers 17 are again moving to the left. As the needles 15 continue to move downwardly the beards are held closed by the presser plate 20 until the tips of the beards pass downwardly through the previously formed loops. As the needles continue to move downwardly the sinkers are moved to permit the new yarn loops to be drawn down past nib portions '65 of the sinkers 17 as shown in Fig. 11. The needles and sinkers then continue to move to the positions of Fig. 6 to complete a knitting cycle.

From the foregoing it will be apparent that the movement of the sinkers derived from the rotation of the shaft and the throw of the eccentric portion 50 thereof acting through the lever 45 and link 41 is so modified by the eccentric portion 57 of the shaft 22 acting through the strap element 51 as to provide the desired synchronization of movement of the sinkers 17 in relation tothe nee- 4 dles 15 and prevent distortion of or strain on the loops. Also, the toggle joint type connection formed by the lever 45 and link 41 between the sinkers and an eccentric shaft rotating at one speed together with the means for modifying the operation of such connection by an eccentric shaft operating at a different speed permits a wide adjustment in the movement of the sinkers 17 to meet specific relationships which may be desired between the needles and sinkers in various points in their paths under different conditions.

It will be understood that the improvements specifically shown and described, by which the above described results are obtained, can be changed and modified in various ways without departing from the invention herein disclosed and hereinafter claimed.

What I claim is:

1. In a tricot knitting machine having spring beard needles, sinkers and eccentric shafts, one of said eccentric shafts operating at a different speed relative to the speed of the other of said eccentric shafts, the combination with means for operating said sinkers including a lever on which said sinkers are supported, a pivotally mounted shaft on which said lever is mounted, a rigid member having one end thereof pivotally mounted on one of said eccentric shafts, a link pivotally connecting the other end of said rigid member and said lever, a strap element having one end pivotally mounted on said other eccentric shaft, and means pivotally connecting the other end of said strap element to said rigid member at a point inter mediate its ends.

2. In a tricot knitting machine having needles, sinkers, and two eccentric shafts, one of said shafts operating at twice the speed of the other of said shafts, the combination with means for operating said sinkers including a lever on which said sinkers are supported, a pivotally mounted shaft on which said lever means is mounted, a rigid member having one end thereof pivotally mounted on one of said eccentric shafts, a link pivotally connecting the other end of said member and said lever, said memher and link having a predetermined relation whereby said lever and sinkers are given a maximum movement by said one eccentric shaft, a strap element having one end pivotally mounted on said eccentric shaft, and means pivotally connecting said strap element to said member at a point intermediate said one eccentric shaft and said link, said other eccentric shaft operating said strap element to vary the relation of said member and link to thereby vary the movement of said sinkers by said one eccentric shaft.

3. In a tricot knitting machine having sinkers, the combination with a first eccentric shaft, a second eccentric shaft, said first eccentric shaft rotating at twice the speed of said second eccentric shaft, a lever supporting said sinkers for oscillation about a fixed axis, a toggle joint, means pivotally mounting one end of said toggle joint on said first shaft, means pivotally connecting the other end of said toggle joint to said lever whereby said first shaft operates said toggle joint to give said lever a predetermined oscillating movement, and means connecting said second shaft to said toggle joint at a point intermediate said first shaft and said lever, said second shaft operating said toggle joint to vary the oscillating movement of said lever by said first shaft.

4. In a. tricot knitting machine having sinkers, a first eccentric shaft and a second eccentric shaft, said first joint at a point intermediate said first eccentric shaft and said lever, said second eccentric shaft operating said toggle joint to vary the oscillating movement of said lever by said first eccentric shaft.

5. In a tricot knitting machine having spring beard needles and sinkers cooperating therewith in loop formation, a shaft having an eccentric bearing portion, means for rotating said shaft at one speed, a second shaft having an eccentric bearing portion, means for rotating said second shaft at a lower speed than that of the first shaft, an oscillatable lever on which said sinkers are supported, toggle means having one end thereof pivotally mounted on said eccentric bearing portion on said first shaft and having the other end thereof pivotally connected to said lever to oscillate said lever, and means driven by said eccentric bearing portion on said second shaft and connecting said toggle means at a point intermediate said first shaft and said lever for modifying the movements of said toggle means.

References Cited in the file of this patent UNITED STATES PATENTS 2,292,287 Peel et a1. Aug. 4, 1942 

